Method and machine for knitting plaited fabric on a circular sinker-top knitting mahcine

ABSTRACT

The stitches of a plaited fabric are formed on a circular sinker-top knitting machine by first feeding one yarn to the hooks of knitting needles located at the knit level and then drawing the yarn down to sinker-throat level where the yarn is held by sinkers as the needles are raised to tuck level, another yarn being there introduced into the hooks of the needles which are then drawn down to form the plaited stitches.

nit tates Patent Inventor Alvin Agulnelr Brooklyn, NY.

Appl. No 822,803

Filed Apr. 4, 1969 Patented June I, 1971 Assignee The Singer Company New York, NY.

METHOD AND MACHINE FOR KNI'I'I'ING PLAITED FABRIC ON A CIRCULAR SINKER-TOP KNITTING MACHINE 5 Claims, 13 Drawing Figs.

US. Cl ..66/9, 66/93, 66/1 36 Int. Cl D04b 9/12, D041) 9/34 Field of Search 66/136, 137, 9, 93

J 1 a 13 1 r l 1 l r I i i 1 1 20 k 4 i 1 1 I a zpi l L/ i l 1 l I i r 1 a/J: 12 eke/2f 38 4o 42 44 46 4a 50 Primary Examiner-Wm. Carter Reynolds Att0rneys-Marshall .l Breen, Chester A. Williams, Jr. and

William V. Ebs

ABSTRACT: The stitches of a plaited fabric are formed on a circular sinker-top knitting machine by first feeding one yarn to the hooks of knitting needles located at the knit level and then drawing the yarn down to sinker-throat level where the yarn is held by sinkers as the needles are raised to tuck level, another yarn being there introduced into the hooks of the needles which are then drawn down to form the plaited stitches.

PATH-HEB JUN 1 IEYI SHEET 1 BF 2 n2. v9. n t N m INVENTOR. Alvm Agulnek WITNESS:

ATTORNE Y PATH-HEB Jun 1 1971 saw 2 or z INVENTOR. AIVII'I Agulnek BY WITNESS:

ATTORNEY METHOD AND MACHINE FOR KNITTING PLAITEI) FABRIC ON A CIRCULAR SINKEII-TOP l(l-llT'I'Il'-lG MACHINE BACKGROUND OF THE INVENTION 1. Field of the Invention The invention relates to the knitting of fabrics on circular sinker'top knitting machines and more particularly is directed to an improved method and machine for knitting plaited fabrics.

2. Description of the Prior Art It has been the practice when knitting plaited fabrics on circular sinker-top knitting machines to simultaneously feed two yarns to the same needles in such a manner that one yarn was fed low across the needles and the other yarn was fed into the hooks of the needles which were then drawn down to form the plaited stitches. The positions of the yarns in the needles and therefore in the stitches of the plaited fabric were controlled by feeding the yarns at different tensions. Such method ofcontrolling the positions of the yarns did not prove to be entirely satisfactory, however, since it did not assure that the yarns would assume the face and rear positions for which they were intended in all stitches of the fabric.

SUMMARY OF THE INVENTION In accordance with the invention plaited stitches are formed on a sinker-top knitting machine by first feeding one yarn for the face side of the stitches (facing yarn) to needles which are at the knit level and which then draw the yarn down to the sinkerthroat level. Such yarn is held by the sinkers as the needles are raised to the tuck position where another yarn for the rear side of the stitches (backing yarn) is introduced into the hooks of the needles. The needles then draw both yarns down to perform their stitching function. Since the yarns are kept completely separate until the stitches are formed, the different yarns always assume their proper positions in the completed fabric.

A principal object of the invention is to provide an improved method and machine for knitting a plaited fabric on a circular sinker top knitting machine which method and machine assure proper positions in the fabric for face and backing yarns.

Another object ofthe invention is to provide a method and machine of the kind described for forming stripe plaiting according to which face and backing yarns are fed to knitting needles through separate striping fingers rather than through a single finger which was the conventional practice and which resulted in the plaiting relationship being disturbed when both yarns were moved simultaneously by the finger.

Still another object of the invention is to provide an improved method and machine of the kind described for forming loop fabric with stripes in the ground yarn.

It is yet another object of the invention to provide an improved method and machine of the kind described whereby the ground yarn in loop fabric may be striped and different loop effects obtained by the use of pattern wheels to vary the operation of sinker cams.

DESCRIPTION OF THE DRAWINGS FIG. I is a schematic view extending over one cam section ofa circular knitting machine constructed according to the invention.

FIGS. 2, 3, 4, 5, 6, and 7 are schematic views showing sequentially the positions into which sinkers are moved with respect to cooperating knitting needles illustrated directly above in FIG. 1.

FIGS. 8, 9, I0, Ill and 12 are perspective views showing the relative positions of sinkers and knitting needles, and additionally showing a portion of fabric knitted according to the invention.

FIG. 13 is a schematic perspective view illustrating the formation of loop fabric according to the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. I of the drawings, reference character 10 designates a portion of the needles of a circular knitting machine, each cam section of which includes elevating cams I2 and 14 for raising the needles to knit and tuck positions respectively and includes depressing earns 16 and 18 for lowering the needles to sinker-throat level and stitching positions respectively. The needles 10 are raised and lowered on actuation oftheir needle butts 20 by the cams as the usual needle carrying cylinder (not shown) rotates in the direction of arrow 22. Alternatively the cylinder may be stationary and the cams mounted on a cylinder for rotation in direction opposite to the direction of arrow 22. Sinkers 24 which are moved by the usual sinker-actuating cams (not shown) cooperate with the needles l0.

Yarn 26 for the face side of plaited stitches to be knitted is fed at each cam section to the needlles 10 which receive the yarn in their hooks when raised to the knit level by cam 12. In the knit position of the needles 10, their latches 13 are open (having been opened by previously formed stitches), and cooperating sinkers are in withdrawn positions with respect to the needles (FIGS. 2 and 8). The needles are drawn down from the knit position by depressing cam 16 until the yarn 26 is at a sinker-throat level (FIGS. 3 and 9), the needle latches being closed by said previously formed stitches in the process. Cooperating sinkers 24 are then moved forward so that the yarn 26 is under the nibs of the sinkers (FIGS. 4 and 10). With the yarn held down by the sinker nibs, needles 10 are raised by elevating cam 14 to tuck position (FIGS. 5 and II) and the needle latches are opened by the yarn 26. Yarn 30 for the rear side of the stitches to be formed is fed to the needles in the tuck position and such yarn is taken into the hooks of the nee dles. With yarn 30 in the hooks of the needles and yarn 26 in the throats of the sinkers, the sinkers are drawn back to clear the yarn 30 from the sinker nibs. The needles are then drawn down to form plaited stitches through the previously formed stitches which close the latches and are cast off (FIGS. 6 and 12.) Since in the described method of knitting the yarns are kept completely separated until stitches are formed, the intended positions for the facing and backing yarns in the plaited stitches are assured.

Two yarns are required at each cam section to knit unstripped plaited fabric in the manner described and if additional suitably colored yarn is available for use in place of one or both of the required yarns, striped plaited fabric may be knitted. Preferably striping is provided for by equipping the knitting machine with two striping boxes 32 and 34 as indicated in FIG. 1 at each of selected cam sections, each such box having a plurality of stripping fingers as 36, 38, 40 and 42 in box 32, and 44, 46, 48 and 50 in box 34 through which yarns of selected colors can be fed to the needles 10. At the cam sections having such striping boxes, yarn is fed through one finger in the one box, such as the: finger 36 in the box 32, to needles in the knit position, and through another finger in the other box, such as the finger 44 in the box 34, to the needles in the tuck position. When it is desired to change the color of a course in the face of the cloth being knitted, the finger feeding yarn for such course to needles in the knit position such as finger 36 in box 32 is withdrawn and another finger in the same box selected to feed a suitably colored yarn to such needles. When it is desired to change the color of a course at the back of the cloth being knitted, the finger feeding yarn for the course to needles in the tuck position such as finger 44 in box 34 is withdrawn and another finger is such box selected to feed yarn of a desired color to these needles. The cloth may be striped on both sides in the same course by withdrawing the fingers normally in use in adjacent boxes associated with a cam section, as for example finger 36 in box 32 and 44 in box 34, and a new finger in each such box selected to feed yarn of a desired color.

The striping boxes which would be associated with yarn cutting and holding devices may be of any suitable type such as that shown, for example, in US. Pat. No. 2,549,701 of Samuel Mishcon issued Apr. 17, l.

The method of the invention may be modified to provide for the formation of loop fabric by having the sinkers 24 remain forward as shown in FIG. 13 when the needles are drawn down by depressing cam 18. The yarn fed to the needles in their tuck position is then kinked over the top of the sinker nib to form loops while the yarn fed to the needles in their knit position is kinked over the normal knitting surface of the sinker to form the body of the fabric.

The yarn for the body of the fabric (ground yarn) may be striped if fed to the needles in the knit position through a striping box having a plurality of fingers which may be selectively operated to supply yarn of a desired color when required. With a pattern wheel acting as a variable sinker cams to select only certain sinkers which are to remain forward when a stitch is formed various loop effects may be obtained.

While the invention has been described in its preferred form, it is to be understood that the words which have been used are words of description rather than of limitation, and that changes within the purview of the appended claims may be made without departing from the true scope and spirit of the invention.

Having thus set forth the nature of this invention, what I claim herein is:

l. A method of knitting plaited fabric on a circular sinkertop knitting machine comprising the steps of raising knitting needles of the machine to a knit position, feeding one yarn for each course of the fabric to be knitted to the needles in said knit position, moving the needles and cooperating sinkers to dispose said one yarn in throats under nibs of the sinkers, raising the needles to the tuck position, feeding another yarn for each course above the sinkers to knitting needles in the tuck position, moving at least some of the sinkers to positions preventing interference of the sinker nibs with the yarns, and

lowering the needles to form plaited stitches in the fabric over the moved sinkers at the level of said sinker throats.

2. A method of knitting plaited fabric on a circular sinkertop knitting machine as defined in claim I wherein the use of at least one of said yarns is discontinued during operation of the machine and a new yarn is fed to the needles in place of the discontinued yarn, the new yarn being of a different color than the discontinued yarn.

3. A method of knitting plaited fabric on a circular sinkertop knitting machine as defined in claim 1 wherein at least some sinkers are at times maintained in the position in which the said one yarn is disposed under their nibs while the needles cooperating with such sinkers are lowered so as to cause the other yarn to form loops over said nibs.

4. In a sinker top circular knitting machine, a plurality of knitting needles, needle actuating means including cams for moving the needles successively to a knit position, sinkerthroat level, a tuck position and a stitch forming position, means for feeding one yarn to the needles when in said knit position, means for feeding another yarn to the needles when in said tuck position, and sinkers cooperating with said needles each sinker including a nib and a single yarn engaging at a level below the level of the nib ledge, the sinkers being movable into positions for holding down the said one yarn under the nibs while the needles are raised to said tuck position and into positions wherein both said one and said another yarn may be drawn over the ledges at said level as the needles move into the stitch forming position.

5. The combination of claim 4 wherein at least one of the yarn feeding means includes a plurality of selectively operable striping fingers through which yarn of a desired color may be fed to the needles. 

1. A method of knitting plaited fabric on a circular sinker-top knitting machine comprising the steps of raising knitting needles of the machine to a knit position, feeding one yarn for each course of the fabric to be knitted to the needles in said knit position, moving the needles and cooperating sinkers to dispose said one yarn in throats under nibs of the sinkers, raising the needles to the tuck position, feeding another yarn for each course above the sinkers to knitting needles in the tuck position, moving at least some of the sinkers to positions preventing interference of the sinker nibs with the yarns, and lowering the needles to form plaited stitches in the fabric over the moved sinkers at the level of said sinker throats.
 2. A method of knitting plaited fabric on a circular sinker-top knitting machine as defined in claim 1 wherein the use of at least one of said yarns is discontinued during operation of the machine and a new yarn is fed to the needles in place of the discontinued yarn, the new yarn being of a different color than the discontinued yarn.
 3. A method of knitting plaited fabric on a circular sinker-top knitting machine as defined in claim 1 wherein at least some sinkers are at times maintained in the position in which the said one yarn is disposed under their nibs while the needles cooperating with such sinkers are lowered so as to cause the other yarn to form loops over said nibs.
 4. In a sinker top circular knitting machine, a plurality of knitting needles, needle actuating means including cams for moving the needles successively to a knit position, sinker-throat level, a tuck position and a stitch forming position, means for feeding one yarN to the needles when in said knit position, means for feeding another yarn to the needles when in said tuck position, and sinkers cooperating with said needles each sinker including a nib and a single yarn engaging at a level below the level of the nib ledge, the sinkers being movable into positions for holding down the said one yarn under the nibs while the needles are raised to said tuck position and into positions wherein both said one and said another yarn may be drawn over the ledges at said level as the needles move into the stitch forming position.
 5. The combination of claim 4 wherein at least one of the yarn feeding means includes a plurality of selectively operable striping fingers through which yarn of a desired color may be fed to the needles. 